1. Technical Field
The present invention relates to a pigment dispersion liquid and a solvent-based ink composition containing the same.
2. Related Art
In the related art, as a technique of forming a coating film having metallic glossy on a printed matter, a foil stamping printing using a printing ink which is produced from brass, aluminum fine particles, or the like and which uses gold powder or silver powder as a pigment or a metal foil, a thermal transfer system using a metal foil, or the like has been used. However, as to those methods, there was a problem in that it was hard to form a fine pattern or apply to a curved surface part. In addition, in a foil stamping printing, there were problems in which on-demand properties were low, it was hard to cope with multiproduct production, and it was difficult to perform metallic tone printing having gradation.
On the other hand, since a powder coating material containing a metal pigment is a low pollution type coating material in which an organic solvent is not used, the demand is increasing in various industries. However, in a case of the powder coating material containing the metal pigment, if it is difficult to array the metal pigment in parallel with respect to a substrate of the coating film, the color tone of the coating film becomes dark, and thus there was a disadvantage in which it was difficult to obtain a sufficient metallic feeling. In order to overcome such a disadvantage, for example, in JP-A-2003-213157 and JP-A-2006-169393, a powder for coating material formed by coating the surface of aluminum particles with a fluorine-based (co)polymer in which a fluorine (meth)acrylic acid ester is set to an essential monomer is disclosed. In addition, in JP-A-2009-215411, a powder for coating material formed by coating the surface of aluminum particles with a fluorine-based copolymer in which a fluorine-based polymerizable monomer and a polymerizable monomer having a phosphate group are set to an essential monomer is disclosed.
In recent years, many application examples of an ink jet method in the printing have been seen, and as an application example among those, there is a metallic printing, and a development for an ink having metallic glossy has been proceeded. In the ink jet method, the metallic printing is excellent in that the metallic printing can suitably be applied for forming a fine pattern or recording to a curved surface part. For example, in JP-A-2012-251070 and JP-A-2013-122008, a composition for an ultraviolet ray curable type ink jet method including metal particles and a polymerizable compound is disclosed.
However, for example, as to aluminum particles formed by coating with a fluorine-based (co)polymer as disclosed in JP-A-2003-213157, JP-A-2006-169393, and JP-A-2009-215411, there was a problem in that the glossiness was reduced due to the process of oxidation of aluminum during a coating treatment. In addition, in a case where such aluminum pigments in which the oxidation is proceeded are dispersed in an organic solvent, there was a problem in that the aluminum pigments were easily flocculated with each other, depending on the external environment. Furthermore, once the aluminum pigments are flocculated with each other, there was a problem in that it was not easy to redisperse the aluminum pigments.
In addition, aluminum pigments and metal particles as disclosed in JP-A-2003-213157, JP-A-2006-169393, JP-A-2009-215411, JP-A-2012-251070, and JP-A-2013-122008 are not ones for the purpose of enhancement in water resistance, however, in a case where these are compounded in a solvent-based ink to record an image, there was a problem in that the weather resistance was not excellent such that an image was whitened by aluminum pigments and metal particles being reacted with moisture in the environment.